Silane end-capped polyarylene polyethers

ABSTRACT

Silane end-capped polyarylene polyethers are disclosed.

The invention relates to silane end-capped polyarylene polyethers.

Thermoplastic polysiloxane-polyarylene polyether copolymers have beendisclosed. For instance, Strachan et al., in U.S. Pat. No. 3,539,655,disclose such copolymers having at least one siloxane chain and at leastone polyarylene polyether chain. Each siloxane chain contains at leasttwo siloxane units of the formula:

        R.sub.b SiO.sub.4-b/2                                                 

wherein b is a number having a value of from 1 to 3, and wherein Rrepresents a monovalent hydrocarbon group, a divalent organic group, oroxy (--0--). The monovalent hydrocarbon groups, which can containsubstituent groups, are substituent groups on the silicon atom, and arebonded thereto by direct carbon-to-silicon bonds. The divalent organicgroups and the oxy groups are the groups that link the siloxane chainsto the polyarylene polyether chains.

Other types of thermoplastic siloxane-polyarylene polyether copolymersare described in Noshay et al., U.S. Pat. Nos. 3,539,656 and 3,539,657.

In a first aspect, the invention provides compositions that compriselinear polyarylene polyether chains that are terminated at both ends byreactive silane end-capping or chain terminating groups. The saidreactive silane groups contain either substituent groups that arehydrolyzable to hydroxyl (silanol) groups, or the silanol groupsthemselves.

In a second aspect, the invention provides a method for "prehydrolyzing"the polyarylene polyethers that contain hydrolyzable silane groups.

In a third aspect, the invention relates to the use of the compositionsof the invention as adhesives and coatings.

In a fourth aspect, the invention relates to the use of the compositionsof the invention as a coupling or sizing agent for mineral fibers suchas fiberglass and asbestos, and to the use of the sized fibers as areinforcing agent in plastic composites.

And in a fifth aspect, the invention provides blends of silaneend-capped polyarylene polyethers with conventional polyarylenepolyethers.

Thermoplastic polyarylene polyethers constitute a known class ofcompositions. For instance, see Johnson et al., British Pat. No.1,078,234; D'Alessandro, U.S. Pat. No. 3,355,272; Darsow et al., U.S.Pat. No. 3,634,354; Rose, U.S. Pat. No. 3,928,295; Newton et al., U.S.Pat. No. 3,764,583; Leslie et al., British Pat. No. 1,369,156; Feasey etal., British Pat. No. 1,348,639; Jones, British Pat. No. 1,016,245; andKing et al., British Pat. No. 1,342,589.

The silane end-capped polyarylene polyethers differ from the knownthermoplastic polyarylene polyethers most significantly in that thecompositions of this invention have reactive silane end-capping groups.In its broadest aspect, the compositions of this invention can berepresented by the formula:

I x -- polyarylene polyether chain -- X' wherein X and X' individuallyrepresent silane groups, each of which contains at least onehydrolyzable substituent group or at least one hydroxyl (silanol)substituent group.

One preferred class of compositions that are within the scope of FormulaI are the silane end-capped polymers that are produced by reacting analkali metal phenoxide end-capped polyarylene polyether with ahalo-substituted hydrocarbylsilane that contains at least onehydrolyzable substituent. These compositions can be represented byFormula II:

Ii (r')₃ si-R-O--Ar-O--_(n) R-Si(R')₃

wherein each R' individually is alkyl or a hydrolyzable group such asalkoxy, dialkylamino, or oxycarbonylalkyl provided that at least one R'on each silicon represents a hydrolyzable group; wherein each Rindividually represents a divalent hydrocarbyl group bonded to thesilicon atom with a direct carbon-to-silicon bond and bonded to the oxy(--0--) group through an aliphatic carbon atom, such as alkylene,cycloalkylene, and aralkylene; wherein n is a positive number andrepresents the degree of polymerization of the polyarylene polyetherchain; and wherein A_(r) represents a divalent aromatic group which canbe the same or a different group from one --Ar-O-- unit to the next, andin which each aromatic group is bonded to the connecting oxy groupsthrough aromatic carbon atoms.

When the compositions of Formula II are reacted with water orhydrolyzed, the hydrolyzable substituent groups are replaced withhydroxy groups.

One convenient way to produce the compositions of Formula II is thefollowing:

Dihydric phenol, such as 2,2-bis(4-hydroxyphenyl)propane("bisphenol-A"), is dissolved in a solvent such as a mixture ofmonochlorbenzene and dimethyl sulfoxide. The dihydric phenol isconverted to the alkali metal salt by adding an alkali metal hydroxide,such as sodium hydroxide, and removing the water of condensation byazeotropic distillation. An aromatic compound having two activated halosubstituents is added to the alkali metal salt. 4,4'-Dichlorodiphenylsulfone is illustrative of such aromatic compounds. The dihalo aromaticcompound is used in a controlled proportion so that there will be astoichiometric excess of the said alkali metal salt. The dihalo aromaticcompound and the alkali metal salt are reacted to form a linearpolyarylene-polyether chain having alkali metal salt end groups. Thiscompound is then reacted with a haloalkyl silane, such as 3-chloropropyltrimethoxysilane, to form a silane end-capped polyarylene-polyether,which is recovered by coagulating the solution in anhydrous methanol oranhydrous isopropyl alcohol.

The foregoing outline of a process for producing the compositions ofFormula II can be represented by the sequence of reactions presentedbelow in which HO-E-OH represents the dihydric phenol and Cl-E'-Clrepresents the dihalo aromatic compound. ##STR1##

The dihydric phenol employed can be a mononuclear compound such ashydroquinone or resorcinol, which may be substituted with an inertsubstituent such as alkyl, alkoxy, or halo.

The dihydric phenol can also be a polynuclear phenol. Examples includep,p'-biphenol, naphthalene diol, alkane bisphenols such asbis(4-hydroxyphenyl)methane and 2,2-bis(4-hydroxyphenyl)propane,bisphenol sulfones such as bis(4-hydroxyphenyl) sulfone, the bisphenolsulfides bis(4-hydroxyphenyl) sulfide, the bisphenol ethers such asbis(4-hydroxyphenyl) ether, and the bisphenol ketones such asbis(4-hydroxyphenyl) ketone.

The preferred dihydric phenols are hydroquinone, bisphenol-A,p,p'-biphenol and bis(4-hydroxyphenyl) sulfone.

The second class of compounds employed are aromatic compounds that havetwo activated halo substituents. The halo substituents are activated sothat, in the absence of a catalyst, the aromatic compound can react withalkali metal phenoxide to form an ether. As is well known in the art,one way to activate the halo substituents is to have an inert electronwithdrawing group ortho or para to the two halo groups. Thehalo-substituted aromatic compound can be a mononuclear compound such as1,2,4,5,-tetrabromobenzene, 1,2,4,5-tetrachlorobenzene, 2,4- and2,6-dichlorobenzonitrile, hexachlorobenzene, and1,4-dibromo-2,3,5,6-tetrachlorobenzene, or it can be a polynuclearcompound such as the following: 4,4'-dichlorodiphenyl sulfone;4,4'-bis(4-chlorophenylsulfonyl)biphenyl; 4,4'-dichlorodiphenyl ketone;3,4,5,3',4',5'-hexachlorobiphenyl;4,4'-dibromo-3,5,3',5',-tetrachlorobiphenyl; and others that are knownto the art.

Other illustrative dihydric phenols and aromatic compounds that containtwo activated halo substituents are disclosed in the patents cited abovethat disclose thermoplastic polyarylene polyethers. These patents areincorporated herein by reference.

In the sequence of reactions (1), (2), and (3), the dihydric phenol isemployed in a stoichiometric excess over the dihalo aromatic compound.Preferably, from about 1.02 to about 1.16 moles of dihydric phenol willbe employed per mole of the dihalo aromatic compound. Within this rangeof proportions, the reduced viscosities in chloroform at 25° C. and at aconcentration of 0.2 gram of polymer per 100 milliliters of solution, ofthe polyarylene polyethers and the silane end-capped polymers derivedtherefrom, will be within the range of from about 0.1 to about 0.5.(Reduced viscosity is determined by the procedure of ASTM-D-2857.)Proportions outside this range can also be used in some cases when it isdesired to produce silane end-capped polymers of either higher or lowermolecular weights.

The sequence of reactions (1), (2), and (3) is the most convenient wayto produce the compositions of Formula II. However, variations of thisprocedure are well within the skill of the art and are contemplated bythis invention. For instance, Reaction (2) can be carried out with anexcess of the dihalo compound (the preferred proportion ofstoichiometric excess being the same as that given above for thedihydric phenol), followed by an alkaline hydrolysis reaction to convertthe halo substituent to alkali metal phenoxide. Then, after azeotropicremoval of water, the product is subjected to Reaction (3) as describedherein. Alternatively, the "single salt process" can be employed (e.g.,as described in Leslie et al., British Pat. No. 1,369,156) to produce apolyarylene polyether terminated at one end by a halo substituent and atthe other by alkali metal phenoxide. Upon alkaline hydrolysis of thehalo group, followed by dehydration, the product can then be subjectedto Reaction (3), as described herein.

In the first step, Reaction (1), the dihydric phenol is converted to thecorresponding alkali metal salt. Two moles of alkali metal hydroxide,such as sodium hydroxide or potassium hydroxide, are reacted per mole ofdihydric phenol. Almost exactly stoichiometric quantities should beused. This reaction is carried out in a solvent system that permitsazeotropic removal of the water of condensation. A mixture ofmonochlorobenzene (MCB) and dimethyl sulfoxide (DMSO) is excellent forthis purpose. The DMSO is used as the solvent, and MCB is an azeotropingagent. Other solvents include dimethylacetamide (DMAC), and otherazeotroping agents include chlorinated benzenes, benzene, toluene, andxylene. The condensation reaction to produce the alkali metal phenoxidewill normally take from about 120 to about 240 minutes at a temperatureof from about 110° to about 132° C. While a much broader temperaturerange is possible, this is the most convenient.

After the water of condensation has been removed azeotropically, thedihalo aromatic compound is added to the reaction mixture to carry outReaction (2). This reaction is carried out at elevated temperature, forinstance, from about 150° to about 170° C., for a period of from about60 to about 120 minutes.

At the completion of Reaction (2), a polyarylene polyether having alkalimetal phenoxide end groups is produced. This composition is reacted witha haloalkyl silane to produce the silane end-capped polyarylenepolyethers of Formula II. Among the haloalkyl silanes that can be usedare the materials enumerated below.

Haloalkyltrialkoxysilanes such as:

3-chloropropyltrimethoxysilane,

3-chloropropyltriethoxysilane,

3-chloropropyltriisopropoxysilane,

chloromethyltrimethoxysilane,

chloromethyltriethoxysilane,

chloromethyltriisopropoxysilane,

2-chloroethyltrimethoxysilane,

2-chloroethyltriethoxysilane,

2-chloroethyltripropoxysilane,

1-chloroethyltrimethoxysilane,

1-chloroethyltriethoxysilane,

1-chloroethyltripropoxysilane,

3-bromopropyltrimethoxysilane,

2-bromoethyltrimethoxysilane, and

bromoethyltrimethoxysilane.

Haloalkyldialkylalkoxysilanes such as:

chloromethyldimethylmethoxysilane, and

chloromethyldimethylethoxysilane

Haloalkylalkyldialkoxysilanes, such as:

chloromethylmethyldimethyoxysilane,

chloromethylmethyldiethoxysilane, and

chloromethylmethyldipropoxysilane.

Haloalkyltrialkanoyloxysilanes such as:

3-chloropropyltriacetoxysilane,

chloromethyltriacetoxysilane,

2-chloroethyltriacetoxysilane,

1-chloroethyltriacetoxysilane,

3-bromopropyltriacetoxysilane, and

2-bromoethyltriacetoxysilane.

Haloalkytri(dialkylamino)silanes such as:

3-chloropropyltri(dimethylamino)silane,

3-chloropropyltri(diethylamino)silane,

chloromethyltri(dimethylamino)silane,

chloromethyltri(diethylamino)silane,

2-chloroethyltri(dimethylamino)silane,

2-chloroethyltri(diethylamino)silane,

1-chloroethyltri(dimethylamino)silane,

1-chloroethyltri(diethylamino)silane, and

2-bromoethyltri(dimethylamino)silane.

Haloaralkyltrialkoxysilanes, such as:

p-(chloromethyl)phenyltrimethoxysilane,

p-(chloromethyl)phenyltriethoxysilane, and

p-(chloromethyl)phenyltrisopropoxysilane.

Haloaralkyltrialkanoyloxysilanes, such as:

p-(chloromethyl)phenyltriacetoxysilane.

Haloaralkyltri(dialkylamino)silanes, such as:

p-(chloromethyl)phenyltri(dimethylamino)silane, and

p-(chloromethyl)phenyltri(diethylamino)silane.

The end-capping reaction, i.e., Reaction (3), is carried out by reactingthe haloalkyl silane with the alkali metal phenoxide-capped polyarylenepolyether produced by Reaction (2). The stoichiometric proportions aretwo moles of silane per mole of polyarylene polyether. It is preferredto employ about a 2 to 10 mole percent stoichiometric excess of thesilane. The reaction mixture should be substantially anhydrous. Thereaction medium can be the same solvent system that was employed forReactions (1) and (2). The reaction is carried out at elevatedtemperatures, e.g., from about 110° to about 165° C. At the recommendedtemperature range, the reaction will usually take from about 10 to about90 minutes.

The completion of the reaction can be detected by treating a sample ofthe reaction mixture with bromocresol purple indicator. When the alkalimetal phenoxide has reacted, the treated sample will be greenish yellowin color.

At the completion of the reaction, the reaction mixture can be cooled,filtered to remove salt by-product, and then the silane end-cappedpolyarylene polyether can be recovered by coagulation in a non-solventfor the polymer, e.g., methanol or isopropyl alcohol. Care should betaken to keep the reaction mixture and the polymer anhydrous until ithas been recovered as a solid, in order to avoid premature hydrolysis ofthe hydrolyzable groups on the silane.

There are alternative ways, using known chemical reactions, to attachthe silane end-capping groups to the polyarylene polyethers chains. Forinstance, the alkali metal phenoxide-capped polyarylene polyethersproduced by Reaction (2) can be neutralized, as by reacting with diluteaqueous hydrochloric acid, to regenerate the phenolic hydroxyl endgroups. After dehydrating, as by azeotropic distillation with MCB ortoluene, the phenolic hydroxyl end-capped polyarylene polyethers can bereacted with two molar equivalents of an isocyanato-substituted silane,or a vicinal epoxide-substituted silane. Specific illustrative knownsilanes that can be used for this purpose include:

3-isocyanatopropyltriethoxysilane,

3-(glycidoxy)propyltriethoxysilane, and

3,4-epoxycyclohexylethyltriethoxysilane.

The reactions that occur in these cases are summarized as follows:##STR2##

Subsequent recovery and use of the silane end-capped polyarylenepolyethers produced by Reactions (4) and (5) are analogous to thatdescribed herein for those produced by Reaction (3).

The Examples set forth below illustrate the practice of the invention.The silane end-capped polyarylene polyethers made from bisphenol-A,4,4'-dichlorodiphenyl sulfone, and 3-chloropropyltrimethoxysilane, areoften referred to as "PSF-SR" (polysulfone-silane reactive).

EXAMPLE 1

This Example illustrates the carrying out of Reactions (1), (2), and(3).

A. Raw Materials

Bisphenol-A -UCC bisphenol A; 99.71% purity. Used without furtherpurification.

Sulfone Monomer (4,4'-dichlorodiphenyl sulfone) -- ICI sulfone monomer;100% purity assumed; used as is.

3-chloropropyltrimethoxysilane -UCC A-143 silane; 97.8% purity.

Sodium Hydroxide -- Mallinckrokt Chemical Works; 98% purity.

Dimethyl Sulfoxide (DMSO) -- Matheson Coleman and Bell.

B. Analytical Methods Determination of sodium phenolate end groups.

This information is needed for determining the amount of3-chloropropyltrimethoxysilane required for the end-capping reaction. Atitration method is used for this purpose.

Upon completion of the polymerization step (Reaction 2), a small sample(about 2 - 3 grams) of the reaction mixture is quickly taken from thevessel and placed in a 250 milliliter Erlenmeyer flask. The sample isweighed and a 50 milliliter solution of DMSO/MCB (1/1) is introduced.The sample solution is heated gently on a hot plate until dissolution iscomplete. A drop of bromcresol purple indicator (0.5 percent inmethanol) is added and the sample is titrated with a 0.1N HCl solution(in DMSO) to a yellow end point (pH 5.2-6.8). Duplicate tests sould bemade.

The amount of sodium phenolate end groups in gram-equivalents, can becalculated from Equation (i):

        Sodium phenolate end groups = (NHCl × NHCl)/1000×(Wt/Ws)                                                                    (i)         

where

Ws = Sample weight in grams

Wt = Total weight of reaction mixture in grams

NHCl = Normality of NCl/DMSO solution.

VHCl = Volume of HCl/DMSO used in milliliters

The amount of 3-chloropropyltrimethoxysilane (m. wt. = 198) needed forthe end-capping, on a 10 percent excess basis, can be calculated fromEquation (ii), where Ps is the purity of the silane used. ##EQU1##

Test for Completion of End-capping Reaction

A 1 or 2 gram sample of the reaction mixture is introduced into a 250milliliter Erlenmeyer flask containing a 50 milliliters solution ofDMSO/MCB (1/1). The sample solution is heated on a hot plate untildissolution is complete. Two drops of the bromcresol purple solution areadded. The reaction is complete if the indicator turns greenish yellowor yellow. Otherwise, the color will be blue indicating the presence ofunreacted sodium phenolate end groups.

C. Preparative Procedure

The following describes the typical procedure used for the preparationof PSF-SR resins.

Into a four-necked, two-liter Morton flask, equipped with a mechanicalstirrer, water trap, condenser, thermometer, addition funnel, and Argoninlet, there was placed 183.16 grams of bisphenol-A (0.8 mole), 350milliliters of DMSO and 700 milliliters of MCB. The slurry was heated to90° C. to give a clear solution. A 50 percent aqueous sodium hydroxidesolution containing 1.6 moles of sodium hydroxide was charged into thereaction vessel. Azeotropic distillation began at around 112° andreached 132° C. (b.p. of MCB) in about three hours. At this point, 108grams of water was collected. Thereafter, MCB was distilled off untilthe reaction temperature reached 150° C. when 593 grams of MCB wascollected. A hot solution of 213.68 grams (0.745 mole) of sulfonemonomer in 230 milliliters MCB was introduced rapidly into the reactionvessel. Distillation of MCB was resumed until the reaction temperatureattained 165° C., when an additional 391 grams of MCB was distilled off.The polymerization was maintained at this temperature for an additional90 minutes. Material balance at this point is shown as follows:

    ______________________________________                                                      Reactor Charge,                                                                            Water Trap                                         Material      grams        Discharge, grams                                   ______________________________________                                        bisphenol-A   183.16                                                          sulfone monomer                                                                             213.68                                                          DMSO          375.2                                                           MCB           1,028.6      984.0                                              NaOH solution 129.96                                                          H.sub.2 O                  110.0                                              Total         1,930.58     1,094.4                                            ______________________________________                                    

There was 838.18 grams of reaction mixture remaining in the vessel andthe polysulfone oligomer concentration was about 47.5 percent.

Samples were drawn from the reaction vessel for sodium phenolateend-group analysis. The average value was found to be 0.1015gram-equivalent.

The reaction mixture was brought to a temperature of 115° C. and 22.23grams of 3-chloropropyltrimethoxysilane [95 percent purity, 5 percentexcess from Equation (ii)] was introduced with a syringe. Care must betaken to prevent atmospheric moisture from getting into the system, andthe maintaining of an anhydrous condition throughout the end-cappingstep is essential to prevent premature gelation. The reaction mixturewas stirred at 115° C. for 75 minutes until the bromcresol purple testbecame greenish yellow in color. Thereafter, the reaction was stopped,and the reaction mixture was cooled down to room temperature. The hazy,viscous solution was diluted with dry MCB to a total solidsconcentration of 28 percent, and was subsequently filtered to give 90.3grams of salt (96.6 percent of the theoretical amount) and a clear,amber-colored filtrate. The latter was poured into a Waring blendercontaining a large excess amount of isopropanol (or methanol) tocoagulate the PSF-SR resin, which was washed with more isopropanol,filtered and was dried in a vacuum oven at 85° C.

    ______________________________________                                        product recovered    324 grams (95.6 per                                                           cent of theoretical)                                     R.V. (in chloroform, at 25° C.                                                              0.26 dl/grams                                            melting point        188-192° C.                                       --Mn (by NMR method) 8,817                                                    ______________________________________                                    

The required end-capping time can be shortened dramatically by addingthe 3-chloropropyltrimethoxysilane at the polymerization temperature. Ahigher end-capping efficiency is also obtained.

When the end-capping step in the above Example was carried out at 158°C. for a period of 30 minutes, the recovered product was practicallyidentical to the one end-capped at 115° C.

    ______________________________________                                        product recovered    216 grams (93.3 per                                                           cent of theoretical)                                     *R.V. (in chloroform at 25° C.)                                                             0.27 deciliters/gram                                     melting point        188-192° C.                                       --Mn (by NMR method) 9,910                                                    ______________________________________                                         *Reduced viscosity- Determined by the procedure of ASTM-D-2857 at a           concentration of 0.2 grams of PSF-SR in 100 milliliters of solution.     

D. Mn Determination

Number average molecular weight (Mn) of the PSF-SR resins is determinedby a nuclear magnetic resonance (NMR) technique using a Varian 100 MHZNMR Instrument. Assuming the PSF-SR resins are completely end-capped,i.e., each molecule is terminated with two silane end groups (and thereis no hydrolysis of the end groups), they are represented by thefollowing general formula: ##STR3## Where n is the number average degreeof polymerization.

Mn and n values of any PSF-SR resins can be calculated from the signalintensities of the gemdimethyl (Hg) and silyl methoxy (Hs) protonsmeasured by the NMR method. ##EQU2##

EXAMPLE 2

The molecular weights of the silane end-capped polyarylene polyethers ofthe invention are largely dependent upon the proportion of dihydricphenol to dihalo aromatic compound employed in the polymerization step,i.e., in Reaction (2). A series of polymers were prepared by proceduresanalogous to that described in Example 1, using varying proportions ofbisphenol-A and sulfone monomer. The solvent systems used were eitherDMSO/MCB or DMAC/MCB. The molecular weights and the values for n in theformula shown in Example 1, were determined by NMR. The reducedviscosities in chloroform were also determined. The results aretabulated in Table I, below.

                                      TABLE I                                     __________________________________________________________________________    PREPARATION AND CHARACTERIZATION OF REPRESENTATIVE PSF-SR                     __________________________________________________________________________    Sulfone/Bis-A           R.V.                                                  Charge Ratio                                                                          Polymerization                                                                         End-Capping                                                                          Chloroform  Recovery,                                 Mole/Mole                                                                             T° C.                                                                      Medium                                                                             T° C.                                                                      .sup.t min.                                                                      25° C.                                                                       n --Mn                                                                              Percentage                                __________________________________________________________________________     0.965  163 DMSO 118 180                                                                              0.42  45                                                                              21,200                                                                            95                                        0.96    163 DMSO 118 180                                                                              0.33  21                                                                              10,000                                                                            95                                        0.98    165 DMSO 115 60 0.46  82                                                                              37,000                                                                            97                                        0.93    164 DMSO 95- 135                                                                              0.26  19                                                                               8,817                                                                            96                                                         115                                                          0.96    170 DMAC  105-                                                                             60 0.37  42                                                                              19,370                                                                            95                                                         110                                                          0.92    165 DMAC 115 60 0.21  17                                                                               8,806                                                                            97                                        0.86    165 DMSO 100 60 0.16   7                                                                               4,112                                                                            94                                        0.93    163 DMSO 140 60 0.29  22                                                                              10,900                                                                            94                                        0.93    163 DMSO 158 30 0.27  20                                                                               9,910                                                                            92                                        0.96    165 DMSO 160 30 0.34        92                                        __________________________________________________________________________

EXAMPLE 3

Into a 1 liter, 4-necked flask, fitted with mechanical stirrer,water-trap, addition funnel, thermometer, and argon inlet, there wasplaced 500 milliliters of dry MCB, and 90.0 grams of a silylmethoxyend-capped polysulfone having the following composition: ##STR4##

The system was thoroughly dried by distilling off 100 milliliters ofMCB. The reaction vessel temperature was lowered to 80° C., and 35.9grams of freshly distilled glacial acetic acid was introduced. Thereaction was maintained at temperatures between 80° and 85° C. for onehour before raising the temperature to refluxing. An additional 100milliliters of solvents were distilled. Thereafter, the temperature waslowered to 65° C., and the polymer recovered by coagulation and repeatedwashing in heptane. After vacuum-drying, a white solid polymer wasobtained. The polymer had a reduced viscosity in chloroform at 25° C. of0.19 deciliters/gram, and would cure rapidly upon heating in a capillarytube. The recovery was 98 percent. On the basis of IR evidence, theproduct contained silyl-acetoxy end-groups, and had the followingformula: ##STR5##

The same polymer can be produced directly by substituting3-chloropropyltriacetoxy silane for the 3-chloropropyltrimethoxysilaneused in Example 1. Since acetoxy groups hydrolyze much more rapidly thanalkoxy groups, the reaction mixture would have to be strictly anhydrouswhen using an acetoxy silane.

EXAMPLE 4

Using the same setup and silyl methoxy end-capped polysulfone describedin Example 3, 90 grams of the polymer and 500 milliliters of dry MCBwere charged into the reaction vessel and heated to reflux. The systemwas thoroughly dried by distilling off 100 milliliters of MCB. Asolution of 0.5 gram glacial acetic acid in 50 milliliter of freshlydistilled isopropanol was rapidly introduced into the reaction vessel.The reaction mixture was refluxed at 96° C. for 2 hours. Thereafter, thetemperature was raised gradually until 100 milliliters of solvent wasdistilled off; this took about 40 minutes. Upon cooling to roomtemperature, the polymer was coagulated in isopropanol, washed, anddried under vacuum. 84 Grams of a white solid polymer was recoverd. Thepolymer had a reduced viscosity in chloroform at 25° C. of 0.18, and amelting point of 168° - 170° C. Analysis by NMR spectroscopy indicatedthat the product contained about 20 percent of silylisopropoxy endgroups.

EXAMPLE 5

Using the same setup and silyl methoxy end-capped polysulfone describedin Example 3, 90 grams of the polymer and 500 milliliters of dry MCBwere charged into the reaction vessel. The polymer solution was heatedto reflux and 100 milliliters of MCB was distilled off to thoroughly drythe system. The vessel temperature was subsequently lowered to 50° C.,when 20 grams of acetyl chloride was introduced. The reaction wasmaintained at 58° to 60° C. for 90 minutes. Thereafter, excess acetylchloride was distilled off by gradually increasing the temperature to129° C. The vessel temperature was lowered to 60° C. and 35 grams offreshly distilled diethylamine was added. The addition was complete inabout 30 minutes. The reaction temperature was again raised gradually bydistilling off the excess diethylamine and MCB until 250 milliliters ofcondensate was collected. Upon cooling to room temperature, the polymerwas coagulated in heptane, washed, and dried under vacuum. A slightlyyellowish solid was obtained. The recovery was 97 percent. The polymerhad a reduced viscosity in chloroform at 25° C. of 0.23 dl/grams, and amelting point of 154° - 158° C. IR and NMR data are consistent with thefollowing silylamino end-capped polymer structure: ##STR6##

EXAMPLE 6

Into a 2 liter, 4-necked flask, equipped with a mechanical stirrer,water trap, addition funnel, thermometer and argon inlet, there wasplaced 174.62 grams (0.8 mole) of 4,4'-thiodiphenol, 500 milliliters ofDMSO, and 700 milliliters of MCB. Upon dissolution at 75° C., a causticsolution containing 64.96 grams (98.5 percent purity) of NaOH and 75milliliters of distilled water was introduced. Azeotropic distillationwas carried out until no more water was produced. A hot, dry MCBsolution containing 215.95 grams (0.753 mole) of 4,4'-dichlorodiphenylsulfone was introduced. The polymerization reaction was maintained at165° C. for 90 minutes. Thereafter, the sodium phenolate end-groupconcentration was determined by titration. A solution of 24.62 grams3-chloropropyltrimethoxysilane in 30 milliliters of dry MCB was added tothe reaction vessel at 165° C. The reaction mixture was held at 165° C.for 30 minutes, and was then brought to room temperature and filtered toremove the salt. The clear, amber-colored filtrate was poured into aWaring blender containing a large excess of isopropanol to precipitatethe polymer. The crude product was washed with isopropanol, filtered,and dried in a vacuum oven at 75° C. A white polymer was obtained, whichhad a reduced viscosity in chloroform at 25° C. of 0.31 and a meltingpoint of 175°-178° C. Spectroscopical data are in agreement with thefollowing structure. ##STR7##

EXAMPLE 7

Into a 2 liter, 4-necked flask, equipped with a mechanical stirrer,water trap, addition funnel, thermometer, and argon inlet, there wasplaced 74.49 grams (0.4 mole) of p,p'-biphenol, 350 milliliters of MCB,and 275 milliliters of DMSO. Upon dissolution at 70° C., a causticsolution containing 32.48 grams of NaOH (98.5 percent purity) and 37.5milliliters of distilled water was added. Azeotropic distillation wascarried out until the reaction medium temperature reached 155° C., whena total of 382.5 grams of distillate had been collected. The temperaturewas lowered to 140° C. and a hot solution of 109.05 grams (0.38 mole) ofsulfone monomer in 125 milliliters of dry MCB was rapidly introduced.Thereafter, the reaction temperature was raised to 165° C. by distillingoff 162.2 grams of MCB, and maintained at this temperature overnight.Next morning, the sodium phenolate end-groups were determined bytitration. A solution of 8.7 grams of 3-chloropropyltrimethoxysilane in30 milliliters of dry MCB was added to the reaction vessel and thereaction mixture was stirred for an additional 30 minutes. End-pointtest showed the reaction was complete. The reaction mixture was broughtto room temperature, diluted with 400 milliliters of MCB, and filtered.Polymer was recovered from the filtrate by coagulation in isopropanol,washed with additional amounts of isopropanol, and dried at 75° C. undervacuum. A white solid was obtained, which had a reduced viscosity of0.40 (measured in chloroform at 25° C.) and a melting point between 225°and 230° C. Its NMR and IR spectra are consistent with the followingstructure: ##STR8##

EXAMPLE 8

Into a 1-liter, 4-necked flask, equipped with a mechanical stirrer,water trap, addition funnel, thermometer and argon inlet, there wasplaced 101.12 grams (0.4 mole) of 4,4'-sulfonyl-diphenol, 510milliliters of MCB, and 250 milliliters of DMSO. Upon dissolution at 75°C., a caustic solution containing 16.24 grams (98.5 percent purity, 0.8mole) of sodium hydroxide and 37.5 milliliters of distilled water wasintroduced. Azeotropic distillation was carried out until thetemperature of the reaction medium reached 155° C. when a total of 290.4grams of distillate was collected. The reaction temperature was loweredto 140° C. and a hot solution of 97.55 grams (0.34 mole) of sulfonemonomer in 12 milliliters of dry MCB was added. An additional 441.8grams of solvent was distilled off to raise the reaction temperature to165° C. It was kept at this temperature for 3 hours. End-capping waseffected by adding a solution of 27.6 grams of3-chloropropyltrimethoxysilane in 50 milliliters of dry MCB into thepolymerization mixture at 165° C. End-point test showed the reaction tobe complete in 40 minutes. The resulting polymer was recovered accordingto the procedure described in Example 7. A white solid was obtained. Therecovery was 91 percent of theoretical. The product had a reducedviscosity in chloroform at 25° C. of 0.074 dl/gm, and a melting pointbetween 155° and 160° C. Its NMR and IR spectra are consistent with thefollowing structure: ##STR9##

EXAMPLE 9

Using an apparatus similar to that described in Example 8, there wasplaced 91.58 grams (0.4 mole) of bisphenol-A, 175 milliliters of DMSO,and 350 milliliters of MCB. Upon heating to dissolution, a solutioncontaining 32.48 grams of sodium hydroxide (98.5 percent purity, 0.8mole) and 325 milliliters of distilled water was added. Azeotropicdistillation was carried out until the temperature reached 155° C. when409.3 grams of distillate had been collected in the water trap. A hotsolution of 104.4 grams (0.364 mole) of sulfone monomer in 125milliliters of dry MCB was added. The polymerization was kept at 164° C.for 90 minutes. Thereafter, the sodium phenolate end-groups weretitrated, and a solution of 11.4 grams (20 percent excess) of3-chloromethyldimethylmethoxysilane in 10 milliliters of dry MCB wasintroduced for the end-capping. The reaction was complete in 30 minutes.After dilution with 400 milliliters of dry MCB, the polymer wasrecovered according to the procedure described in Example 7. A whitepowdery solid polymer was obtained. The recovery was 90 percent oftheoretical. The polymer had a reduced viscosity measured in chloroformat 25° C. of 0.22 dl/gm. Its NMR and IR spectroscopic data areconsistent with the following structure: ##STR10##

EXAMPLE 10 Model Reaction Bis(trimethoxysilylpropyl) derivative ofBisphenol-A

In a 500 cc 4-neck flask fitted with stirrer, thermometer, droppingfunnel, and Y tube with N₂ inlet tube and helices-packed fractionatingcolumn with water trap and condenser, were placed the following:

    ______________________________________                                        22.83 grams Bisphenol-A .1 mole                                               45 milliliters DMSO                                                           55 milliliters toluene                                                        ______________________________________                                    

air was displaced by nitrogen and 16.02 grams 49.94 percent NaOH (.2mole) was added. The mixture was refluxed, removing water until no morewas evident; then toluene was distilled off to a pot temperature of 160°C. The mixture was cooled to 120° C. and 43.7 grams Cl(CH₂)₃ Si(OCH₃)₃(.22 mole) was added. Heating was continued at 115°-120° C. for 11/2hours until test showed that no residual alkalinity remained. Theproduct was filtered through an M porosity sinter glass funnel, and thesalt cake was washed with dry toluene. The toluene-DMSO solution waswashed repeatedly with water to extract DMSO, then the toluene andtraces of water were removed by distillation under vacuum, finally to150° C./1 mm pressure.

The residue product was obtained as a clear pale liquid, yield 52.9grams (theoretical: 55.3). Analysis showed 0.006 percent OH bypoteniometric titration, and NMR analysis showed the correct ratio (2/6)of Bisphenol-A to siloxane methyls.

EXAMPLE 11 Model Reaction Bis(trimethoxysilylpropyl) derivative ofBisphenol-S

The same apparatus and procedure as in Example 10 was used with thefollowing:

    ______________________________________                                        25.03 grams 4,4'-Dihydroxydiphenyl sulfone                                                               0.1 mole                                           60 milliliters DMSO                                                           85 milliliters toluene                                                        16.04 grams 49.90 per cent NaOH                                                                          0.2 mole                                           ______________________________________                                    

The bisphenol disodium salt was dehydrated as before and most of thetoluene was distilled. The mixture was cooled and there was added:

43.7 grams 3-chloropropyltrimethoxysilane -- 0.22 mole .

The reaction mixture was heated a total of 21/2 hours at about 130° C.to complete the etherification. The product was filtered to removesodium chloride, and the salt was washed with dry toluene. Saltrecovered-11.6 grams (theoretical: 11.69). The filtrate was washedrepeatedly to remove DMSO, then the toluene was removed by distilling asin Example 10. The yield of light colored viscous liquid product was56.1 grams (theoretical: 57.48).

EXAMPLE 12 Silane End-Capped Bis S Polyether:

In an apparatus similar to that described in Example 10, the followingwere placed:

    ______________________________________                                        25.03 grams 4,4'-Dihydroxydiphenyl sulfone                                                               .1 mole                                            70 milliliters DMSO                                                           100 milliliters toluene                                                       air was displaced by N.sub.2 and:                                             16.03 grams 49.90 per cent NaOH                                                                          .2 mole                                            ______________________________________                                    

added. The mixture was refluxed, removing water until no more wasevident, then toluene was distilled off to a pot temperature of 160° C.,and a solution of:

    ______________________________________                                        24.15 grams 4,4'-Difluorodiphenyl sulfone                                                              .095 mole                                            33 milliliters dry chlorobenzene                                              ______________________________________                                    

added. The mixture was heated with stirring at 160°-170° C. for 21/2hours to complete the oligomerization, then cooled to 130° C. and:

3.0 grams Cl(CH₂)₃ Si(OCH₃)₃ -- 0.15 mole

added. Heating was continued at 130° C. for 13/4 hours to complete theend capping reaction. The product was diluted with 100 milliliters ofdry monochlorobenzene and filtered through a medium porosity sinteredglass funnel. The clear, colorless filtrate was coagulated in methanolusing a Waring blender, and the granular white powder washed furtherwith methanol, filtered, and dried in a vacuum oven.

Yield: 39 grams (theoretical: 47 grams)

RV_(NMP) = 0.49 (in N-methylpyrollidone at 25° C.)

To partially hydrolyze the siloxane end methoxyls, 10 grams of thepolymer was slurried in a 20 percent aqueous solution of acetic acid andheated with stirring at 60° C. for 11/2 hours, then washed free of acidand vacuum dried. RV_(NMP) - 0.67. The partially hydrolyzed siloxanepolymer cured appreciably faster on molding than did the originalpolymer.

EXAMPLE 13 Silane end-capped Bis A -- Difluorobenzophenone polyether

In an apparatus like that described in Example 10 were placed thefollowing:

    ______________________________________                                        22.83 grams Bisphenol A .1 mole                                               70 milliliters DMSO                                                           80 milliliters toluene                                                        Air was displaced by nitrogen and there was added:                            15.85 grams 50.48 per cent NaOH                                                                       .2 mole                                               ______________________________________                                    

The mixture was refluxed, removing water until no more was evident, thentoluene was distilled off to a pot temperature of 150° C. A solution of:

    ______________________________________                                        20.51 grams 4,4'-Difluorobenzophenone                                                                   .094 mole                                           in 20 milliliters dry chlorobenzene                                           ______________________________________                                    

was gradually added. On adding the last increment of thedifluorobenzophenone, the polymer viscosity became very high, but oncontinued heating at about 160° C. for 11/2 hours it decreased somewhat.The mixture was diluted with dry chlorobenzene and cooled to about 140°C., and a total of 4.3 grams Cl(CH₂)₃ Si(OCH₃)₃ (0.22 mole) added.Heating was continued at 130°-140° C. until test showed no residualalkalinity. The mixture was diluted further with dry chlorobenzene,filtered, and the clear filtrate coagulated in methanol as in Example12.

Yield = 30.7 grams (41.5 theo)

RV CHCl₃ = 0.66

Clear colorless solutions of polymer (20 percent) in THF(tetrahydrofuran) were made up. The solution without additive remainedstable for weeks, whereas one treated with a trace of dibutylindilaurate gelled within 8 hours, and another with trifluoroacetic acidgelled overnight at room temperature.

In a major aspect of the invention, the alkoxy-, alkanoyloxy-, ordialkylamino- silane end-capped polyarylene polyethers are hydrolyzed toform silanol end-capped polyarylene polyethers. It is well known thatthe following reactions take place: ##STR11## It is also known thatsilano groups can condense to form siloxane groups:

        Si-OH + HO-S → Si-O-Si + H.sub.2 O               (9)           

the combination of the hydrolysis reaction and condensation reaction canbe employed to cure the silane end-capped polyarylene polyethers of theinvention to form cross-linked polymers. Curing can be effected inseveral different ways. For instance, the solid polymer can be heated toa temperature above its glass transition temperature, e.g., to atemperature of from about 150° C to about 350° C., for a period of about1 to about 100 minutes, preferably under pressure (a pressure range offrom contact pressure, e.g., about 1 to 3 psi, to about 600 psi or more,is recommended except for coating applications, where no pressure isused). Trace amounts of moisture, which is inevitably present from theatmosphere (the polymer will absorb atmospheric moisture), initiate thehydrolysis reaction. The silanol groups then condense to generate morewater, which further propagates the two reactions.

The condensation reaction proceeds at a much faster rate than thehydrolysis reaction. However, when the resin is in the solid state, therigid polymeric backbone prevents the silanol groups from interacting toany great extent. Therefore, a two-step curing process is possible. Thesolid resin, in finely divided form, can be "prehydrolyzed", in aqueousmedium at a temperature that is below the glass transition temperatureof the polymer. The subsequent silanol end-capped polymer can thereafterbe heated above its glass transition temperature to effect cure.Theprehydrolysis procedure is illustrated in the following Example:

EXAMPLE 14 Prehydrolysis of PSF-SR*

Prehydrolysis of the PSF-SR resins is carried out in an aqueoussuspension to minimize the risk of premature gelation. A catalyst suchas acetic acid is used. (Bases and metal soaps will also catalyze thehydrolysis and condensation reactions, as is known in the art.) Thefollowing describes the typical procedures used for this transformation.

A. To a solution consisting of 50 grams of acetic acid and 950milliliters of distilled water was added 100 grams of a PSF-SR (R.V. =0.29, Mn = 10,900) resin in fine powdery form. The slurry was heated toa temperature for a period of 3 hours. Thereafter, the reaction mixturewas cooled to room temperature and the resin was collected byfiltration. The crude product was washed twice with an excess ofisopropanol in a Waring blender to remove the absorbed acetic acid. Theproduct was collected and dried at 85° C. under vacuum. The recovery waspractically quantitative.

The prehydrolyzed PFR-SR resin is physically identical to its precursor.At this stage it remains thermoplastic and is soluble in all PSF-SRsolvents. NMR analysis showed that 23 percent of the silane end groupsin the above product were hydrolyzed.

B. To a boiling aqueous acetic solution composed of 120 grams of aceticacid and 1080 milliliters of distilled water was charged 120 grams of aPSF-SR resin (R.V. = 0.45). The fluff was kept in suspension throughvigorous stirring. After 30 minutes refluxing at 100° C., the resin wasseparated by filtration. Working through the same recovery stepsdescribed above, 118 grams of product was obtained. The resultingproduct had a R.V. of 0.48 and was shown to be 20 percent hydrolyzed byNMR analysis.

Glass Transition Temperatures

The glass transition temperatures were determined by using aDifferential Scanning Calorimeter for PSF-SR resins having variousnumber average molecular weights. The results are plotted on the graphshown on FIG. 1. The correlation between number average molecular weightand reduced viscosity (at 25° C., in chloroform) is shown in the graphcontained in FIG. 2. The procedure for using the Differential ScanningCalorimeter is described by A. Duswalt, "Industrial Research," July1975, pp. 42-45.

The following group of Examples further illustrates the hydrolysis andcondensation reactions:

EXAMPLE 15

The polymer prepared in Example 4 was compression molded at 600 psi and200° C. for 30 minutes followed by an additional 60 minutes at 275° C. Atough, clear, amber-colored plaque was obtained. The cured plaqueexhibited good stress-crack resistance to organic solvents.

EXAMPLE 16

The silylacetoxy end-capped polymer prepared in Example 3 wascompression molded at 275° C. under a pressure of 1,000 psi for 10minutes. The cured plaque was clear, amber-colored and was no longersoluble in chloroform. It exhibited good mechanical strength and a muchimproved stress-crack resistance to organic solvents than conventionalthermoplastic polysulfone resins.

EXAMPLE 17

The polymer prepared in Example 6 was cured by compression molding at600 psi and 275° C. for 15 minutes. A clear, amber-colored plaque wasobtained. The plaque had the following mechanical and thermalproperties:

    ______________________________________                                        Tensile modulus, psi   259,000                                                Tensile strength, psi  7,900                                                  Yield strength, psi    7,900                                                  Elongation at break, per cent                                                                        5.5                                                    Pendulum impact, ft-lb/in.sup.3                                                                      55                                                     Tg,° C.         125                                                    Modulus at 250° C., psi                                                                       1,000                                                  ______________________________________                                    

It also exhibited good stress-crack resistance to organic solvents.

EXAMPLE 18

A 12 gram quantity of the reactive polysulfone prepared in Example 8 wascompression molded at 600 psi and 275° C. for 10 minutes to give a 4inch × 4 inch × 20 mil plaque. The latter was clear, yellow-colored, andfairly brittle. Solubility test showed the plaque to be highly cured.

EXAMPLE 19

A slurry containing 20 grams of the product prepared in Example 9, 10grams of glacial acetic acid, and 80 milliliters of distilled water washeated to refluxing (100° C.) while under vigorous stirring. After 2hours of refluxing, the hydrolyzed polymer was recovered by filtering,washing with isopropanol, and drying under vacuum at 75° C. 19 grams ofthe hydrolyzed polymer having a reduced viscosity of 0.21 dl/gm wasrecovered. The presence of silanol end-groups in the product wasconfirmed by the NMR data, which coresponds to the following structure.##STR12##

EXAMPLE 20

12 grams of the polymer prepared in Example 7 was compression molded at600 psi and 320° C. for 10 minutes to give a 4 inch × 4 inch × 20 milplaque. The plaque was transparent, and brown-colored. It was tough andexhibited good stress-crack resistance to organic solvents. Itsmechanical and thermal properties are as follows:

    ______________________________________                                        Tensile modulus, psi   211,000                                                Tensile strength, psi  9,500                                                  Yield strength, psi    9,500                                                  Yield Elongation, per cent                                                                           9                                                      Elongation at break, per cent                                                                        11                                                     Pendulum impact, ft-lb/in.sup.3                                                                      99                                                     Tg, ° C.        215                                                    Modulus at 300° C., psi                                                                       700                                                    ______________________________________                                    

EXAMPLE 21 Rate of Hydrolysis Measurement

The rate of hydrolysis of PSF-SR resins in an aqueous suspension, shownin FIG. 3 and Table II, below, was measured with two independentanalytical methods.

1. GC Method -- Using a 5 milliliter vial fitted with a "Teflon"-linedaluminum cap, there was placed 0.5 gram of PSF-SR (R.V. = 0.3) and 5milliliters of a 5 percent (by volume) aqueous acetic acid solution. Thesealed vial was shaken vigorously to suspend the resin particles.Thereafter, the sample was heated in a constant temperature bath at 80°C., (± 0.1° C.) for a specified time. After quenching, samples werewithdrawn with syringe for the GC analysis. A Perkin-Elmer 990 FlameIonization Gas Chromatograph fitted with a "Carbowax"-coated "Teflon"(40/60 mesh) packed column was employed. The amounts of methanol andmethyl acetate were determined. The percent of hydrolysis was measuredby the amount of methanol evolved.

2. NMR Method -- The hydrolyzed PSF-SR resins as described above wererecovered by filtering and washing with isopropanol. After vacuumdrying, the samples were analyzed by NMR as described in Section D,Example 1. The percent of hydrolysis was calculated from a decrease inthe Hs/Hg signal intensity ratio.

                  TABLE II                                                        ______________________________________                                        HYDROLYSIS OF PSF-SR.sup.a END                                                GROUPS AT 80° C. IN 5 PER CENT ACETIC ACID                             ______________________________________                                                 Per Cent Hydrolysis                                                  Time Hrs.  By GC Method  By NMR Method                                        ______________________________________                                        0.25       5.4            6                                                   0.50       7.6           11                                                   1.0        10.3          16                                                   1.5        11.5          17                                                   2.0        15.7          17                                                   3.0        20.4          24                                                   5.0        30.3          28                                                   21.0       77.3           52.sup.b                                            ______________________________________                                         ##STR13##                                                                    .sup.b Partially gelled in chloroform; may not represent                       the whole sample.                                                        

EXAMPLE 22

The mechanical and thermal properties of three crosslinked PSF-SR resinshaving initial R.V. ranging from 0.24 to 0.45 dl/gm. together with thoseof a standard polysulfone are listed in Table III. The PSF-SR resinswere molded at 600 psi and 300° C. for 30 minutes. The standardpolysulfone was molded at 600 psi and 300° C.

                  TABLE III                                                       ______________________________________                                        MECHANICAL AND                                                                THERMAL PROPERTIES OF CROSSLINKED PSF-SR                                      ______________________________________                                                                            Commercial                                Sample No.    1       2       3     Polysulfone*                              ______________________________________                                        Initial R.V. dl/gm.                                                                         0.45    0.30    0.24  Control                                   Tensile Modulus, psi                                                                        261,000 267,000 250,000                                                                             280,000                                   Tensile Strength, psi                                                                       10,210  10,000  8,980 10,500                                    Yield Strength, psi                                                                         10,210  10,000  8,980 10,500                                    Yield Elongation, per                                                                       8       8       8     8                                          cent                                                                         Elongation at Break,                                                                        10      9       9     25                                         per cent                                                                     Notched Izod Impact                                                                         1.22    --      2.02  1.3                                        Ft.-lbs./Inc.                                                                Pendulum Impact                                                                             123     49      97    196                                        Ft.-lbs./In..sup.3                                                           Tg, ° C                                                                              165     170     160   180                                       Modulus at 250° C., psi                                                              900     1,100   1,400 Very low                                  ______________________________________                                         *The commercial polysulfone used here and in other Examples as a control      is the reaction product of bisphenol-A and 4,4'-dichlorodiphenyl sulfone,     having a Melt Flow at 650° F.(343° C.) and 44 psi (by ASTM      1238) of about 6.5 decigrams/minute.                                     

The tensile properties of the PSF-SR resins are comparable to those ofthe standard polysulfone. Their lower elongations at break areindicative of a crosslinked structure. There is insufficient data atthis moment to show any trend in impact properties which appear to beinfluenced by both the crosslinking density and by the initial molecularweight. Roughly speaking, their Izod impact strengths are equal orbetter, and their pendulum impact strengths are lower than those ofstandard polysulfone. In comparison with some conventional thermosets,such as the epoxy resins, the PSF-SR resins show good retention of thetoughness of the base polysulfone. This behavior is significant becausea high crosslinking density, which is essential for providing a goodenvironmental stress-crack resistance, can be realized with the PSF-SRresins without much trade-off in toughness. A plausible explanation isthat in a PSF-SR network, the rigid PSF chains are linked togetherthrough the very flexible siloxane bonds. Consequently, even at highdegrees of crosslinking, some molecular mobilities are still possible.

Owing to the presence of siloxane units, cured PSF-SR resins possess asomewhat lower Tg than the standard polysulfone. However, they retain aresidual modulus at temperatures well beyong the Tg. The magnitude ofthis residual modulus is a measure of the crosslinking density. As shownin Table III, above, the value increases with decreasing initial R.V. ofthe resins. This is expected because higher crosslinking densitiesshould result from resins having lower initial molecular weights. Atypical E-T (modulus-temperature) curve of the PSF-SR resins, togetherwith that of a standard polysulfone, are shown in FIG. 4.

The effects of varying crosslinking densities on the properties of aPSF-SR resin are clearly demonstrated by the data shown in Table IV,below, where the Tg and moduli at 250° and 350° C. are related to theswelling index and percent extractable values. Swelling Index equals thevolume of swollen gel/volume of unswollen polymer (after extraction).Extractables equals weight of boiling methylene chloride-solubleportion/total weight of cured resin.

                                      TABLE IV                                    __________________________________________________________________________    CHARACTERISTICS OF CROSSLINKED PSF-SR                                         Sample       Swelling                                                                           Extractables,                                                                         Tg,                 Cure                            Description  Index                                                                              Per Cent                                                                              ° C.                                                                       250° C., psi                                                                   350° C., psi                                                                   Conditions                      __________________________________________________________________________    0.38 Initial R.V.,                                                                         6.0  19.8    155 570     800     600 psi, 300° C.,        Thermally Cured                               20 minutes                      0.38 Initial R.V.,                                                                         3.1  1.3     175 1,260   1,320   600 psi, 275°-           Prehydrolyzed and                             300° C.,                 Thermally Cured                               20 minutes                      50/50 Blend  6.4  56.4    170 410     200     600 psi, 275° C.,        Commercial Polysulfone                        15 minutes                      0.27 Initial R.V.,                                                            Thermally Cured                                                               __________________________________________________________________________

Under identical curing conditions, the prehydrolyzed sample produced amuch higher crosslinking density as evidenced by the markedly lowerswelling index and extractables. It also exhibited a significantlyhigher Tg as well as higher moduli at elevated temperatures.

Also included in Table IV are properties of a sample composed of a 50/50blend of Commercial polysulfone/0.27 initial R.V. PSF-SR. Thiscompatible blend gave a Tg slightly below that of the commercialpolysulfone, but retained some residual modulus at much highertemperatures.

EXAMPLE 24

Environmental stress-crack resistance data were measured using 1/8-inchstrips of the compression molded specimens at constant stress levelsusing an environment of solvent-saturated cotton swabs attached to thespecimens. The time elapsed at a given stress level before ruptureoccurrred was recorded. Three solvents commonly used by the coatingindustry were studied. Results are listed in Table V.

                                      TABLE V                                     __________________________________________________________________________    ENVIRONMENTAL STRESS-CRACK RESISTANCE                                                                       Toluene    Trichloroethylene                                                                        Acetone                   __________________________________________________________________________    Sample      Cure       Extractables                                                                         Stress                                                                            t to Rupture                                                                         Stress                                                                            t to rupture                                                                         Stress                                                                            t to Rupture          Description Conditions %      Psi.                                                                              Min.   Psi.                                                                              Min.   Psi.                                                                              Min.                  __________________________________________________________________________    0.38 Initial R.V.                                                                         600 psi, 275-300° C.,                                                              1.3   1000                                                                              180.sup.a                                                                            2000                                                                              53     2000                                                                              240.sup.a             Prehydrolyzed                                                                               20 minutes                                                      Thermally Cured                                                               0.38 Initial R.V.                                                                         600 psi, 300° C.,                                                                 19.8   1000                                                                              24     2000                                                                              31     2000                                                                              12                    Thermally Cured                                                                             20 minutes      2000                                                                              15                                          50/50 Blend 600 psi, 275° C.,                                                                 56.4   1000                                                                              3 sec. 1000                                                                              48     2000                                                                              8                     Commercial poly-                                                                            15 minutes       500       2000                                                                              14                               sulfone/0.27 Initial                                                          P.V. PSF-SR                                                                   Commercial  600 psi, 300° C.,                                                                 Soluble                                                                               200                                                                              Instantaneous                                                                         200                                                                              10 sec.                                                                              2000                                                                              Instantaneous          polysulfone                                                                  __________________________________________________________________________     .sup.a Test discontinued at this point.                                  

PSF-SR resins were shown to exhibit a dramatic improvement inenvironmental stress-crack resistance over the standard polysulfone. Theextent of improvement increases with increasing crosslinking densitieswhich were indicated here by percent extractables. Interestingly, anoticeable improvement was realized even with a 50/50 blend ofcommercial polysulfone/PSF-SR. Optimum performance, however, can beachieved only with neat PSF-SR resins at high crosslinking densities.

EXAMPLE 25

Polysulfone is well known for its excellent electrical properties whichshould be reflected by the PSF-SR. A comparison of electrical propertiesof these two polymers is shown in Table VI. The PSF-SR resins were curedat 600 psi and 300° C. for 15 minutes.

                  TABLE VI                                                        ______________________________________                                        ELECTRICAL PROPERTIES OF PSF-SR                                                                        Commercial                                                          PSF-SR.sup.a                                                                            Polysulfone                                          ______________________________________                                        Dielectric Strength,                                                           Volts/mil.      380         425                                              Arc Resistance,  124         122                                               seconds                                                                       Tungsten Electrodes                                                          Volume Resistivity                                                                             1.3 × 10.sup.16                                                                     5 × 10.sup.16                               at 72° F, ohm-cm                                                      Dielectric Constant                                                                            9.69        3.07                                              at 74° F                                                               60 cps-1 mc                                                                  Water Absorption,                                                                              0.7         0.3                                               per cent in 24 hours.                                                        ______________________________________                                         .sup.a 0.45 initial R.V., a pilot plant-produced sample containing            abnormally high amount of residual alkalinity which could have adversely      affected the measured electrical properties.                             

PSF-SR resins were found to absorb twice as much water as the standardpolysulfone. This result is surprising because siloxane linkages formedby the end groups are hydrophobic. A plausible explanation is that thecured PSF-SR resins still contain unreacted silanol groups which wouldresult in higher hydrophilicities.

As illustrated by the foregoing Examples, cured PSF-SR resins retainmuch of the properties of the parent polyfulfone. In addition, theyoffer a dramatically improved environmental stress-crack resistance, apotential high-use temperature, and much desired adhesive properties(discussed below). All of the above properties are, however, stronglyinfluenced by the finished network structures.

ADHESIVE PROPERTIES

Owing to the chemical nature of the silane end groups, silane end-cappedpolyarylene polyether resins exhibit markedly improved adhesiveproperties compared with standard polysulfone.

In order to obtain optimum adhesive performance with standardpolysulfone, metal substrates must be thoroughly cleaned, often by usingan acid or an alkali etch, and the adhesive joints must be bonded usingvery high temperatures of the order of 700° F. Therefore, despite thefact that acceptable adhesive strength can be obtained with standardpolysulfone in many cases, it has not been successful commercially inadhesive applications because of the stringent requirements for its use.In the experiments presented in this section, the metal substrates weresubjected only to a solvent wipe to degrease them. Therefore, it must bekept in mind that the poor adhesion shown for the standard polysulfonecontrols could be improved considerably, but only by using thecommercially undesirable means of etching the metal substrates, andbonding at much higher temperatures.

The silane end-capped resins possess three important features which areabsent from the standard polysulfone. First, the presence ofhydrolyzable silane end groups provides an inherent coupling ability tomany inorganic and metallic surfaces; second, the silane end-cappedresins have a much lower melt (or solution) viscosity which greatlyfacilitates "wetting" during the formation of adhesive joints; andthird, once cured, silane end-capped resins will offer better creepresistance at elevated temperatures.

The usefulness of silane end-capped resins as a structural adhesive isillustrated by its ability to bond the aluminum substrates shown inTable VII. Strong adhesive joints also have been made with a variety ofother substrates including glass, steel, copper, and somesilicon-containing polymers. The first two speciments were preparedusing a 3-10 mil film PSF-SR interlayer. The film was prepared bypressing the resin powder at about 200 psi for 5 minutes at 190° C. Theadhesive joints were held together under contact pressure (about 5-10psi) during the cure. The PSF-SR prime coating for the third specimenwas applied from methylene chloride solution.

                                      TABLE VII                                   __________________________________________________________________________    ADHESIVE PROPERTIES OF PSF-SR                                                 Substrate(s) Cure Conditions                                                                         Strength                                                                              Remarks                                        __________________________________________________________________________    Aluminum/PSF-SR                                                                            270° C., 1 hr.                                                                   28 lbs/in.                                                                            2-3 lbs/in. with                                (0.36 R.V.)           (T-peel).sup.a                                                                        standard polysulfone                           Clad Aluminum Alloy/                                                                       270° C., 1/2-1 hr.                                                               4,700 psi                                                                             Comparable to Epoxy/                            PSF-SR (.33 R.V.)     (Lap Shear).sup.b                                                                     polyamide structural                                                          adhesive                                       Commercial Polysulfone                                                                     240° C., 10 min.                                                                 23 lbs/in.                                                                            3 lbs/in. with standard                         Foam/Aluminum.sup.c   (T-peel).sup.a                                                                        polysulfone                                    __________________________________________________________________________     .sup.a Tested at 2"/min. cross-head speed.                                    .sup.b ASTM-D-1002.                                                           .sup.c PSF-SR used as a prime coating.                                   

To prepare strong adhesive joints, the silane end-capped polyarylenepolyether interlayer must possess good wettability and high cohesivestrength. While wetting is normally not a problem for solution-basedapplications, high R.V. resins (>0.45) are not recommended forapplications where a melt process is contemplated. This is because oftheir inadequate melt flows which tend to result in poor wetting duringbonding. On the other hand, very low R.V. PSF-SR resins (<0.2) havelittle initial mechanical strength and must be substantially advanced tobuild up a satisfactory cohesive strength.

The above considerations are illustrated by the following experiment. APSF-SR resin was hydrolyzed to different extents to yield products ofvaried melt flows and cure speeds. Peel strengths of aluminum/aluminumjoints bonded with each of the above resins were measured and listed inTable VIII. The PSF-SR resins were applied as powder interlayers, whichfused to form a continuous film during cure.

                  TABLE VIII                                                      ______________________________________                                        ADHESIVE PROPERTIES OF PSF-SR RESINS HAVING                                   DIFFERENT INITIAL M. WTS. AND CURE SPEEDS                                     Hydrolysis.sup.a                Peel Strength.sup.d                           Condition    R.V..sup.b                                                                            Cure Speed.sup.e                                                                         Lbs./In.                                      ______________________________________                                        Control      0.28    Slow       10                                            5 per cent Acetic                                                                          0.3-0.4 Fairly Fast                                                                              30                                             Acid                                                                         10 per cent Acetic                                                                         0.4-0.5 Fast       31                                             Acid                                                                         25 per cent Acetic                                                                         0.5.sup.c                                                                             Very Fast   6                                             Acid                                                                         ______________________________________                                         .sup.a Hydrolysis was carried out at 100° C. for a period of two       hours.                                                                        .sup.b Measured in chloroform at 25° C.                                .sup.c Only partially soluble in chloroform                                   .sup.d Measured with Instron at a cross-head speed of 2" per minute.          .sup.e All joints cured at 275° C. for a 10-minute cycle at about      100 psi.                                                                 

The control was apparently undercured and its low cohesive strength isreflected by the much lower peel strength value observed. A similar weakjoint resulted when a highly hydrolyzed resin was used. In this instancepoor wetting is believed to be the cause. When an adhesive joint isprepared under conditions so that the PSF-SR interlayer would providenot only an adequate melt flow initially but also a highly curedcomposition at the end, a good joint strength is usually ensured.

Preparation of Adhesive Joints

For this purpose, the silane end-capped polyarylene polyether may beapplied either as an adhesive interlayer or as a prime coating on thesubstrates. The recommended procedures are the following:

1. As adhesive interlayer - the silane endcapped resins may be meltfabricated into films at a temperature below or around 200° C. withoutany noticeable advancement. At this uncured stage the film is ratherbrittle and is particularly so for films made from resins having a R.V.below 0.25. On the other hand, too high a R.V. is not desirable becausea lack of melt flow may lead to poor wetting during the bondingoperation. Usually, resins having a R.V. range 0.28 - 0.35 arepreferred. Bonding is effected at a temperature of 250° C. or above, andthe required curing cycle time decreases with increasing temperature.Some pressure is necessary to ensure a good wetting and is especially sowith the higher R.V. resins. Contact pressure up to about 600 psi forfrom 3 to 60 minutes is recommended.

2. As prime coatings -- silane end-capped polyarylene polyethers aresoluble in all polysulfonesoluble solvents. Because of their much lowermolecular weights, silane end-capped resin solutions of high solidcontents can be prepared conveniently. Besides solution coating, powderor aqueous-emulsion coating techniques could also be applicable. Forsolution coatings, a silane end-capped resin may be used as is, orprehydrolyzed, or in the presence of a catalyst. Depending on thecoating formulation, a broad range of baking conditions may be employed.Useful solvents include chlorinated hydrocarbons, dioxane, andtetrahydrofuran. Substrates include metals such as aluminum, aluminumalloys, stainless steel, carbon steel, tin and tin-plated metals, andcopper; inorganic materials such as glass; and plastics such aspolysulfone. Useful curing conditions will usually be found within theranges of 160° to 300° C., contact pressure to 600 psi, and 3 to 60minutes.

EXAMPLE 26

Two sheets of 25 mil thick aluminum test panels were joined with a 3 - 5mil thick film interlayer of the reactive polysulfone prepared inExample 7. The joint was cured by compression molding at 100 psi and275° C. for 15 minutes. The finished laminate was cut into one-inchwidth strips and tested for peel strength. Using an Instron machine, theaverage peel strength was measured to be 14.5 lbs./in. at a cross-headspeed of 2 inches per minute.

The solutions coatings referred to above may be used in adhesiveapplications, or as surface coatings. The latter is illustrated in thefollowing example:

EXAMPLE 27

A coating solution was made with 20 grams of the silylamino end-cappedpolysulfone in Example 5 and 80 milliliters of cyclohexanone. Thesolution was applied on a 25 mil thick aluminum test panel andsubsequently baked at 265° C. for 15 minutes in an air oven. A clear,tough coating was obtained, which had good stress-crack resistance toacetone or toluene as well as excellent adhesion to the aluminumsubstrate.

Sizing and Coupling Agents for Fiberglass Reinforced Plastics

In addition to its potential as a matrix resin, silane end-cappedpolyarylene polyethers can be useful interfacial agents, particularlyfor composites based on polysulfone. For this purpose, it may be appliedeither as an integral blend, due to its compatibility with the standardpolysulfone, or onto the fiberglass as a coupling and sizing agent. Ithas been shown that a temporary aqueous emulsion of the silaneend-capped resins may be prepared with the aid of a polar solvent, suchas tetrahydrofuran, and a surfactant. However, polymer separationusually results after overnight standing.

Some mechanical and thermal properties of the polysulfone laminates inwhich the glass cloth was treated with PSF-SR are shown in Table IX. Thesignificant improvement in heat distortion temperature and flexuralstrength and the lowering in notched impact strength are consistent withthe anticipated greater fiber/matrix adhesion. Consequently, an evengreater beneficial effect may be realized in short glass fiberreinforced polysulfone composites where a higher fiber/matrix adhesionshould result in an improvement in fracture toughness.

                  TABLE IX                                                        ______________________________________                                        PROPERTIES OF PSF-SR TREATED GLASS CLOTH.sup.a                                REINFORCED POLYSULFONE LAMINATES                                              ______________________________________                                        Glass, % by wt. (plies)                                                                        30 (5)      30 (5)                                           Treatment        PSF-SR.sup.b                                                                              None                                             Flexural Strength psi                                                                          29,200      21,700                                           Flexural Modulus × 10.sup.-6                                                             1.09        0.97                                              psi                                                                          Tensile Strength psi                                                                           17,900      17,600                                           Modulus of Elasticity                                                                          1.16        1.11                                              × 10.sup.-6 psi                                                        Elongation %     1.57        1.82                                              Izod Impact Strength                                                                          3.7         5.4                                               ft.-lb./in. Notch                                                             HDT at 264 psi, ° C.                                                                   196         187                                              ______________________________________                                         .sup.a OCF-181 heat-cleaned glass cloth.                                      .sup.b Treated with a 2% THF solution of PSF-SR (R.V. = 0.45) and followe     by a half-hour bake at 150° C.                                    

EXAMPLE 28

The effectiveness of the silane end-capped polyarylene polyethers as asizing or coupling agent for glass fiber reinforced polysulfone wascompared with that of the best commercially available sizing presentlyavailable for that purpose. The materials used, experimental procedure,and results are shown below.

    ______________________________________                                        MATERIALS USED                                                                ______________________________________                                        A-1100  H.sub.2 NCH.sub.2 CH.sub.2 CH.sub.2 Si(OC.sub.2 H.sub.5).sub.3                                  Union Carbide Corp.                                 A-1111  (HOC.sub.2 H.sub.4).sub.2 NCH.sub.2 CH.sub.2 CH.sub.2 Si(OC.sub.2             H.sub.4).sub.2        72% active in                                                                  ethanol                                                                  Union Carbide Corp.                                 P-1700  Polysulfone Resin Union Carbide Corp.                                 1581-112                                                                              Heat cleaned Fiberglass                                                        fabric           J.P. Stevens Co., Inc.                              PSF-SR-1   RV = 0.51                                                          PSF-SR-2   RV = 0.24                                                          PSF-SR-3   RV = 0.17                                                          ______________________________________                                    

FABRIC FINISHING

One weight percent active ingredients of A-1100 and A-1111 silane wereprepared in water and used to finish 1581-112 fiberglass fabric. Fabricfinished with the PSF-SR were prepared in THF at a 2 wt percent solidsconcentration. The treated fabric was air dried 20 minutes followed by a2.5 minute heat set at 135° C.

COMPOSITE PREPARATION

a. Resin: P-1700 polysulfone resin was dissolved in methylene chlorideto a solids content of 20.4 wt percent.

b. Prepreg: The desired fiberglass fabric was treated with the abovementioned polysulfone solution, air dried 3 hours, followed by a 1 hourheat set at 50° C.

c. Lamination: Eleven ply of the prepreg were used to prepare thecomposites. Composites were pressed 20 minutes at 550° F. and 200 psipressure using "Teflon" film as a release.

TESTING

Flexural strengths and tangential modulus of elasticity were determinedinitially and after a 16 hour immersion in 50° C. water according toASTM designation D-790-71. The results are displayed below in Table X.

                                      TABLE X                                     __________________________________________________________________________    PHYSICAL PROPERTIES OF POLYSULFONE LAMINATES REINFORCED                       WITH SILANE-FINISHED GLASS FABRIC                                             __________________________________________________________________________           Silane             Per Cent                                                                             Flexural Strength                                                                       Tangential Modulus                        Per Cent     Reduced                                                                             Water  (Psi × 10.sup.-3)                                                                 (Psi × 10.sup.-6)            Silane Concentration/Solvent                                                                      Viscosity                                                                           Absorption.sup.1                                                                     Initial                                                                            Wet.sup.1                                                                          Initial                                                                            Wet.sup.1                     __________________________________________________________________________    Control                                                                       (no silane)                                                                          --           --    1.01   20.2 18.4 1.40 1.30                          A-1100 1.0/H.sub.2 O                                                                              --    1.21   41.6 41.9 1.73 1.49                          A-1111 1.0/H.sub.2 O                                                                              --    0.34   53.1 49.0 1.97 1.98                          PSF-SR-1                                                                             2.0/THF      0.51  0.25   42.6 38.8 1.93 1.66                          PSF-SR-2                                                                             2.0/THF      0.24  0.16   53.3 50.6 2.24 2.18                          PSF-SR 3                                                                             2.0/THF      0.17  0.17   44.4 41.8 1.89 1.77                          __________________________________________________________________________     .sup.1 After a 16 hour immersion in 50° C. water.                 

Extrusion and Melt Fabrication

The silane end-capped polyarylene polyether resins may be meltfabricated at temperatures much below those normally used for thestandard polysulfone because of their much lower glass transitiontemperatures. They were extruded successfully in a laboratory extruderat temperatures between 200° and 250° C. depending on their initial R.V.No premature gelation was encountered during the extrusion. However, agradual advancement in molecular weight appeared to have taken placeduring the extrusion, particularly with those samples which containedresidual alkalinity.

Usually, the melt fabrication methods are not recommended for formingthe prehydrolyzed materials because of the latter's high cure speedswhich severely restrict the extrusion (or molding) latitude.

Melt fabricated PSF-SR articles can be cured in a hot mold or in apost-cure operation, e.g., at 250° to 350° C. for 3 to 60 minutes.

In analogy to the standard polysulfone, the silane end-capped resinsmust be predried before any melt fabrication in order to elminate thetendency of foaming due to the absorbed moisture.

Emulsification

A solution consisting of 5 grams of a PSF-SR resin (R.V. = 0.23) and 20milliliter of THF (or any other suitable solvent) was poured into ahigh-speed Waring blender containing 500 milliliters of distilled water.The blending was continued for 10 minutes to produce a uniform emulsion.However, polymer separation took place during overnight standing.

The emulsion stability may be improved by the addition of a suitablesurfactant such as a non-ionic surfactant. Long chain alkylphenolethoxylates, long chain alkyl ethoxylates, and poly(ethyleneoxide)/(propylene oxide) block copolymers are illustrative. The aqueousemulsions can be used as sizing for glass, asbestos, or other mineralfibers, and in adhesives and coatings.

EXAMPLE 29 CATALYTIC CURING OF PSF-SR

Mixtures consisting of 10 grams of powdered PSF-SR (standardcomposition, 0.23 R.V.) and a specified amount of a suitable catalystwere dry blended thoroughly in a mortar. The formulations weresubsequently compression molded at 50 psi to a 10 mil thick plaque. Thelatter were tested for solubility in chloroform and stress-crackresistance in an acetone environment. The results are shown below inTable XI.

                                      TABLE XI                                    __________________________________________________________________________    Catalyst         Curing Condition                                             __________________________________________________________________________    Type     Concentration                                                                         T, ° C.                                                                    t, min.                                                                            Observation                                         __________________________________________________________________________    HEXA,    1%      220 20   Became only slightly soluble                        (hexamethylene-           in chloroform,; improved stress-                    tetramine)                crack resistance to acetone.                        Ammonium 1%      220 10   Insoluble in chloroform; Improved                   Carbonate                 stress-crack resistance to acetone.                 Para-Toluene-                                                                          1%      220 10   Limited solubility in chloroform;                   sulfonic Acid             Improved stress-crack resistance                                              to acetone                                          Control          220 20   Remained soluble in chloroform;                     (no catalyst)             poor stress-crack resistance                        __________________________________________________________________________

The catalytic effect of the above reagents is evidenced by a reductionin chloroform solubility and an improvement in stress-crack resistanceof the molded plaques containing them. Under similar molding conditions,the control sample showed practically no curing taking place.

EXAMPLE 30 (Hydrolysis)

A PSF-SR resin having an R.V. of 0.39 (chloroform, 25° C.) washydrolyzed with a 10% aqueous acetic acid solution at 100° C. for aperiod of 30 minutes. The recovered resin was shown by NMR technique tobe 26% hydrolyzed. A plaque compression molded at 250° C. (15 min., 600psi) was strong, insoluble in chloroform and resistant to acetone.

EXAMPLE 31 (Coating)

A clear solution containing 20 parts (by wt.) of the hydrolyzed PSF-SRprepared in Example 30, and 80 parts of chloroform was prepared.Coatings on a variety of substrates were made under differentconditions, and their properties examined. Results are shown in TableXII.

                                      TABLE XII                                   __________________________________________________________________________               Substrate Type                                                                Aluminum          Copper     Window                                Drying Conditions                                                                        Q-panel  Shim Steel                                                                             0.007" sheet                                                                             Glass (1/8")                          __________________________________________________________________________    Room Temperature                                                                         clear, smooth                                                                          clear, smooth                                                                          Same as    Same as                               (overnight)                                                                              coating; good                                                                          coating; good                                                                          Aluminum   Aluminum                                         adhesion; low                                                                          adhesion; low                                                        solvent resist-                                                                        solvent resist-                                                      ance     ance                                                      130° C.                                                                           clear, smooth                                                                          Same as  Same as    Same as                               (2 hrs.)   coating; good                                                                          Aluminum Aluminum   Aluminum                                         adhesion;                                                                     improved solvent                                                              resistance                                                         260° C.                                                                           clear, smooth                                                                          Same as  Yellowish, smooth                                                                        clear, smooth                         (2 hrs.)   coating; good                                                                          Aluminum coating; good                                                                            coating; good                                    adhesion; good    solvent resistance;                                                                      adhesion; good                                   solvent resist-   low adhesion due                                                                         solvent resistance                               ance              to copper oxidation                              260° C.                                                                           --       --       --         became slightly                       (16 hrs.)                               yellowish in color;                                                           coating remained                                                              intact.                               __________________________________________________________________________

The above 260° C. baked coatings were found to be highly cured asevidenced by their insolubility in chloroform. After 16 hr. heat agingat 260° C., in an air oven the coating remained strong and tough.

EXAMPLE 32 (Injection molding and post curing)

A 50/50 blend of PSF-SR (R.V. = 0.27) and a commercial polysulfone wasextruded with an 1-Foot singlescrew extruder operating at a temperaturebetween 260° to 310° C., and was pelletized to give a uniformcomposition. The pellets were injection molded using a Van DorneInjection Machine at 358° C. The barrel residence time was about 3minutes, and the mold temperature was maintained at 115° C. Theinjection molded parts were clear, glossy, and without any physicaldefects. They remained, however, soluble in chloroform under thesemolding conditions.

The injection-molded parts were post-cured using either an air oven oran acid (or base) bath. For instance, a 21/2 inches = 1/2inch = 1/8inchspecimen was heated in an air oven at 275° C. for a period of 35minutes. The baked specimen became only partially soluble in chloroformand exhibited a substantially improved stress-crack resistance inacetone. Similar improvement also was obtained by placing the specimenin a boiling water bath containing 2-10% acetic acid.

EXAMPLE 33

PSF-SR resin (R.V. = 0.36) was compression molded at 220° C. (200 psi,30 min) to form a 20 mil thick plaque. The latter was laminated with a 4inches × 1 inch × 1/16 inch titanium panel at an initial temperature of220° C. and a finish temperature of 270° C. The total heating timelasted for 55 min., and only contact pressure was used. After cooling toroom temperature the specimen gave an 8 lbs/inch L-peel strength whenmeasured with a Hunters Spring. Under similar laminating conditions,adhesion between commercial polysulfone and titanium was below 1pound/inch.

EXAMPLE 34 (Catalytic curing with a metal soap)

One hundred parts of a PSF-SR resin (R.V. = 0.18) was thoroughly blendedwith 2 parts of a tin soap (GE RTV-5300B). The above formulation wasspread on an aluminum Q-panel and heated at 210° C. for about 10minutes. During the heating, the resin particles fused and formed acoherent film which was no longer soluble in chloroform, and whichexhibited good environmental stress-crack resistance. When no metal soapwas used, the resin remained thermoplastic after being subjected to thesame thermal treatment.

EXAMPLE 35 (Catalytic curing with Hexa)

A series of PSF-SR (R.V. = 0.45) formulations containing 0.6, 1.2 and1.8% by weight of Hexa were prepared by dry blending 25 parts of thepowdered resin with a 3% Hexa solution in methanol at loadings of 5, 10,and 15 parts, respectively. Methanol was subsequently removed in avacuum oven at 45° C. The dried mixes were molded separately into 4inches × 4 inches × 20 mil plaques at 200° C. under a pressure of 400psi for a 10-minute cycle. All three plaques were cured, as evidenced bytheir insolubility in chloroform and good environmental stress-crackresistance in acetone. A control, which contained no Hexa, showed verylittle cross-linking when it was molded under the same conditions.

EXAMPLE 36 (Catalytic curing with Hexa)

The PSF-SR formulation containing 1.2% by weight of Hexa described inExample 35 was laminated between two 25-mil thick aluminum Q-panels at200° C. for 10 minutes under a pressure of 400 psi. The finishedlaminate was cut into one-inch width strips for T-peel strengthmeasurement with an Instrom machine at a cross-head speed of 2inches/minute. A value of 8.5 pounds/inch was obtained. Without Hexa,the PSF-SR would be expected to react very slowly under theseconditions, and a much lower adhesion would result.

EXAMPLE 37 (Hexa-catalyzed coatings on aluminum foil)

Four parts each of three PSF-SR resins having R.V. values of 0.24, 0.30and 0.45, respectively were dissolved in 20 parts of dichloroethanecontaining 1 part of a 3% Hexa solution in methanol. Aluminum foilstrips (5 inches × 3/4inch × 0.005 inch) were coated with each of thethree solutions by dipping and air drying. These coatings weresubsequently cured in an air oven at 260° C. for a period of 20 minutes.Coatings made from all three solutions were cured, and exhibitedexcellent adhesion, impact resistance, and solvent resistance.

EXAMPLE 38 Production Of Polysulfone-Siloxane Block Copolymers

The mono-silanol end-capped polysulfone of Example 19 can be used formaking polysulfone/polysiloxane block copolymers.

Fifteen parts of the mono-silanol end-capped polysulfone (Mn = 6,800)prepared in Example 19 were dissolved in 100 parts of MCB containing 0.1part, by weight, of sodium methoxide. The solution was heated torefluxing temperature under a nitrogen blanket. A solution of 15 partsof a hydroxyl-terminated, polydimethylsiloxane (Mn = 1,352) in 25 partsof MCB was introduced into the reaction vessel. MCB was slowly distilledoff until a total of 64 parts of condensate was collected in 5 hours.The latter contained about 1 part of water. The reaction mixture wasallowed to cool down to room temperature. The top layer, which containedmostly unreacted silicone oil, was discarded. The bottom layer wascoagulated in isopropyl alcohol, washed with additional isopropylalcohol, collected, and was dried under vacuum at 60° C. 13.5 Parts of awhite solid resin was recovered which had a R.V. of 0.45 (chloroform,25° C.). IR and NMR data of the product were consistent with theintended polysulfone/polysiloxane block copolymer structure. Thecopolymer was analyzed to contain 17% by weight of silicone.

What is claimed is:
 1. A silane end-capped polyarylene polyether of theformula:X--polyarylene polyether chain--X'wherein X and X' individuallyrepresent silane end groups, wherein each silane end group contains atleast one hydrolyzable substituent group or at least one silanolhydroxyl group.
 2. The silane end-capped polyarylene polyether of claim1 wherein the hydrolyzable substituent is alkoxy, dialkylamino, oroxycarbonylalkyl.
 3. The silane end-capped polyarylene polyether ofclaim 1 wherein said polyarylene polyether contains alkoxy, silanolhydroxy, or both, substituents on the silicon atoms of the silanegroups.
 4. The silane end-capped polyarylene polyether of claim 1 whichis a composition of the formula:(R')₃ Si-R-O--Ar-O--_(n) R-Si(R')₃wherein each R' individually represents alkyl, alkoxy, dialkylamino, oroxycarbonylalkyl substituent groups and at least one R' on each siliconatom represents a hydrolyzable group; wherein each R individuallyrepresents a divalent hydrocarbyl group bonded to the silicon atom witha direct carbon-to-carbon bond, and bonded to the oxy group through analiphatic carbon atom; wherein n is a positive number; and wherein Arrepresents a divalent aromatic group that can be the same or differentfrom one --Ar-O-- group to the next, and in which each Ar group isbonded to the connecting oxy groups through aromatic carbon atoms. 5.The silane end-capped polyarylene polyether of claim 4 wherein each Rindividually represents alkylene, cycloalkylene, or aralkylene.
 6. Thesilane end-capped polyarylene polyether of claim 4 wherein at least someof the hydrolyzable substituents on the silicon atoms have been replacedwith hydroxy groups.
 7. The silane end-capped polyarylene polyether ofclaim 5 wherein at least some of the hydrolyzable substituents on thesilicon atoms have been replaced with hydroxy groups.
 8. The silaneend-capped polyarylene polyether of claim 4 which is a composition ofthe formula:(R')₃ Si-R-O-E--O-E'-O-E--_(n) O-R-Si(R')₃ wherein n, R, andR' have the meanings stated in claim 4; wherein E represents the residueafter removal of the hydroxyl groups of a dihydric phenol; and whereinE' represents the residue after removal of the two activated halo groupsof an aromatic compound having two activated halo substituents.
 9. Thesilane end-capped polyarylene polyether of claim 8 wherein each Rindividually represents alkylene, cycloalkylene, or aralkylene.
 10. Thesilane end-capped polyarylene polyether of claim 8 wherein at least someof the hydrolyzable substituents on the silicon atoms have been replacedwith hydroxy groups.
 11. The silane end-capped polyarylene polyether ofclaim 9 wherein at least some of the hydrolyzable substituents on thesilicon atoms have been replaced with hydroxy groups.
 12. The silaneend-capped polyarylene polyether of claim 8 wherein E represents theresidue of hydroquinone, 2,2-bis(4-hydroxyphenyl)propane,4,4'-thiodiphenol, p,p'-biphenol, or bis(4-hydroxyphenyl) sulfone, andwherein E' represents the residue of 4,4'-dihalodiphenyl sulfone,4,4'-dihalobenzophenone, or 4,4'-bis(4-halophenylsulfonyl)biphenyl. 13.the silane end-capped polyarylene polyether of claim 8 wherein Erepresents the residue of 2,2'-bis(4-hydroxyphenyl)propane, and whereinE' represents the residue of 4,4'-dihalodiphenyl sulfone.
 14. The silaneend-capped polyarylene polyether of claim 8 wherein R representsalkylene, and wherein the hydrolyzable R' groups are alkoxy.
 15. Thesilane end-capped polyarylene polyether of claim 14 wherein at leastsome of the alkoxy groups have been replaced with hydroxy groups. 16.The silane end-capped polyarylene polyether of claim 9 wherein Erepresents the residue of hydroquinone, 2,2-bis(4-hydroxyphenyl)propane,4,4'-thiodiphenol, p,p'-biphenol or bis(4-hydroxyphenyl) sulfone, andwherein E' represents the residue of 4,4'-dihalodiphenyl sulfone,4,4'-dihalobenzophenone, or 4,4'-bis(4-halophenylsulfonyl)biphenyl. 17.The silane end-capped polyarylene polyether of claim 9 wherein Erepresents the residue of 2,2-bis(4-hydroxyphenyl)propane, and whereinE' represents the residue of 4,4'-dihalodiphenyl sulfone.